[WIP] API improvements

Hey @marksteele !!! :smiley:

This patch add some improvements :

#####  Add maven/jetty integration
* Keep the application easily compatible with others web containers
* Start the server by ```mvn jetty:run``` ;)
* Servlets  are configurable by ```webapp/WEB-INF/web.xml```

#####  Add [Jersey](https://jersey.java.net/) rest api
* Easier to add new resources/services
* Easier to consume

#####  Add [Spring](http://www.springsource.org/spring-framework) DI
* Provides a good way to manage configurations
* Provides a dependency injection container